The first cut (LGD1) stored every tile of every layer raw, scale channel and all: 288 MB a map, which
made Maroon's pack 803 MB. LGD2 keeps a tile index per layer (8 bytes a tile, read whole at the map's
load): 0 all zero, 1 one value in the word, else an offset and a length, the top bit set when the bake
deflated it (inflated into the tile cache with the runtime's z_inflate, a reused buffer; nothing per
frame beyond the cache). A layer keeps its scale only where it varies, the density 6 bits and the scale
4 (the same integer arithmetic as the bake). The bake is maroon-lake's tools/bake/ground_density.py;
the dev copy here writes the same format stored. Maroon 23.2 MB, Lamar 17.2 MB.
The deflated flag is tested as a negative length: `b & 0x80000000` compiled to broken IR (an i32
`and` with a bare `-`), a compiler fault to fix separately.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
ground_density_bake(path, key, version, hash, pngs) cuts each layer's PNG (R the chance a cell keeps one,
G an optional scale) into the terrain's 64 m tiles, one layer decoded and let go at a time, as a bake's
file; ground_density_open(...) reads it - or, when it is missing or stale, a dev build's own copy cut from
the PNGs - a tile at a time into a 256-tile clock, never a layer whole. ground_fill(s, cx, cz, band, g)
places a GroundFill row's instances in a stream chunk: a candidate per cell of the band's step, jittered,
kept when a hash of (layer, chunk, band, cell) falls under the density (times the game's trample,
r3d_on_ground_trample, where the row asks); scale, yaw, seed and wind from the same hash. Nothing calls
it yet: behaviour unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
